For techies only!

[jbird]

Lately, while playing my Dual Rec at bedroom levels, the volume will drop! If I turn the volume knob up, there's a sudden increase, not linear! I've been told to clean the effects loop jacks! I don't use the effects loop, (the knob on the back is in bypass)! How would this fix my problem?

 

[fdesalvo]

Is this behavior exhibited at moderate volume levels? It sounds like you may have the master set so low that the preamp is unable to pass a clean enough signal. On top of this, the difference in volume between 0 and 1 may seem abrupt at bedroom levels.

~F

 

[NoGlassNoClass]

Try turning up the master and using the channel vol to turn down...maybe not your ideal tone but its just for low-vol practice right? Not sure but I think on the 2-channel, the FX loop has to be active for the master vol to work

 

[jbird]

OK, it's not that there's a volume drop at first, there seems to be a point in the lower volume regions where a slight nudge up will release a sort of pop and jump in volume, then it will decrease again at once, I'll move the volume knob up again, and same thing happens! Does it on both channels, effects loop on or off! I might suspect power tubes, but they've been changed (along with all the tubes), the problem persists! I once heard cleaning the effects loop jacks is the cure-all! Just wondering how that would work?

 

[fdesalvo]

Hey, you can spray some contact cleaner on a patch of cloth and put it around the tip of a guitar cable. Now vigorously insert and remove this into each jack. Voila! Check the cloth for signs of corrosion!

~F

 

[coop21]

I had a similar problem and it turned out to be the volume pot. You could try cleaning it. I pulled mine out and checked it with a meter. I called Mesa tech support and they sent me a new one. I replace it and the problem was solved.

 

[NoGlassNoClass]

... a sort of pop and jump in volume

+1 on the volume pot.

 

[jbird]

Happens on both channels! Never noticed this before, could it be an area in volume the amp just is'nt happy at! Crank it up and it's fine! Try playing at condo levels, she's not happy!